The move empowers his Health secretary to suspend federal requirements and speed treatment. More than 20,000 hospitalizations have been confirmed as H1N1 infections since April.

WASHINGTON — President Obama on Saturday declared the swine flu outbreak a national emergency, a procedural step designed to allow healthcare providers to speed treatment and slow the spread of the disease.

The action gives Secretary of Health and Human Services Kathleen Sebelius temporary authority to grant waivers that would expedite steps such as setting up off-site emergency rooms to treat potential flu victims apart from other patients.

Administration officials said the move was not made as a result of any particular development, but as a preemptive measure to ensure that the tools for a quick response were in place.

"The potential exists for the pandemic to overburden healthcare resources in some localities," the White House announcement said. "Thus, in recognition of the continuing progression of the pandemic, and in further preparation as a nation, we are taking additional steps to facilitate our response."

According to the Centers for Disease Control and Prevention, 46 states have reported widespread incidence of the swine flu, also known as H1N1. Since the outbreak of the pandemic in April, there have been more than 20,000 hospitalizations from laboratory-confirmed infections and more than 1,000 deaths.

The declaration is the second step in the government's response effort. In late April, HHS declared a public health emergency, which allowed the government to release antiviral medications from federal stockpiles to states that might need them.

The national emergency declaration allows Sebelius, on a case-by-case basis, to waive federal rules governing routine medical operations if requested by doctors or hospitals.

For example, to isolate infected patients, some hospitals are planning to establish separate treatment locations in off-site tents or community centers. But without a waiver of current rules, the hospital may not get federal reimbursement if the facility is too far from its property. Hospitals could also ask for a waiver of paperwork procedures if they are besieged by flu patients.

"If there's a surge in patients, you want to be able to put in place more efficient methods of triaging and treating people," said Reid Cherlin, a White House spokesman. "It's a priority for providers not to have to waste time on the phone with federal managers."